I use 4gig myself (Extreme III)...I can't remember anyone using more than 4gig (people are worried about any more than that if they lose it or it dies). Most likely it's possible, but not the best thing.

That was my strategy last May when I went to Paris. Took several 1 GBCF cardsas backups formy own E300and my girlfriend's Canon S410 and dumped to a Wolverine 40GB image tank every evening. Wound up keeping a 4 GB Sandisk card in mine, which was good for around 280+ RAW files. We wound up dumping 27GB worth of files to it over the two week trip and it worked great. I'll be doing the same thing again this September when we go back there.

I have an issue with using any CF card lager than 2gig.
It just take too long to transfer from the CF card to my Epson p-2000 Portable Media Storage.
So I carry at least 6 CF cards varying from 1gig to 2gig max. Tom